ProcessID, ThreadID
These properties of the _VFP
application object, added in VFP 6 SP3, return the Windows
ProcessID and ThreadID.
Usage
|
nThreadID = _VFP.ThreadID
nProcessID = _VFP.ProcessID
|
Starting a program in Windows creates a process. Each
process has a numeric ID associated with it. (Go into the Task
Manager, select the Processes tab, and you'll see the Process ID,
or PID). Within each process, there is at least one thread. A
thread shares the process' virtual address space and system
resources. A single-threaded application has one thread; a
multithreaded application has many threads that can appear to run
at the same time using preemptive multitasking (available in
Windows NT and later). VFP is, practically speaking, a
single-threaded application for its main logic, although it does
spawn a couple of "helper" threads on occasion.What does this
mean to your application? Mostly, it explains how it runs, and
you don't have to worry about it. Now, if you're writing COM
objects, you'll likely need to understand a little more about it.
For more information on this, see the Help file topic,
"Scalability and Multithreading." Using the ProcessID and
ThreadID properties can help you debug COM objects. You can also
pass these values to certain Windows APIs for more functionality,
for example, to kill a process.
Example
|
nThreadID = _VFP.ThreadID
nProcessID = _VFP.ProcessID
|
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